The effects of steel, polypropylene, and high-performance macro polypropylene fibers on mechanical properties and durability of high-strength concrete

Present study aimed to compare the properties of high-strength and ordinary concrete containing polypropylene fibers (PPFs), high-performance synthetic macro polypropylene (HPP) fibers, and steel fibers (SF) under standard and sulfate curing conditions. The high-strength concrete with water-to-cement ratios of 0.38, 0.33, and 0.28 were tested. The addition of PPF and SF reduced the workability of these mixtures containing supplementary cementitious material. The highest compressive strength belongs to the mixture containing 1% of SF and 0.2% of PPF. The highest tensile strength belongs to the mixture containing 0.5% of HPP fibers with 1% of SF and 0.2% of PPF. The highest flexural strength of the mixture containing 0.5% of HPP fibers with 1% of SF. Fiber-reinforced concretes have less 30-minute water absorption than non-fiber samples. The minimum absorption belongs to the sample containing 0.5% of PPF with 20% of silica fume in the amount of 0.53%.

Automated summary

The study compared the properties of high-strength and ordinary concrete with different types of fibers (PPFs, HPP fibers, and SF) under standard and sulfate curing conditions. The addition of PPF and SF reduced the workability of the mixtures containing supplementary cementitious material. The mixture with 1% SF and 0.2% PPF showed the highest compressive strength, while the mixture with 0.5% HPP fibers, 1% SF, and 0.2% PPF showed the highest tensile strength. The flexural strength was highest in the mixture with 0.5% HPP fibers and 1% SF. Fiber-reinforced concretes had lower 30-minute water absorption compared to non-fiber samples, with the sample containing 0.5% PPF and 20% silica fume showing the lowest absorption of 0.53%.